Automatic self-starter for motors.



LH. H. CUTLER.

AUTOMATIGISBLF STARTER POR MOTORS. urLmuIoN'rILnD APB. a, 1904.l BBNEWBDMAR. 2.9, 1912.

.Patentedflvom 5, 1912.

2 slums-s111121 1.

H. H. CUTLB-R. AUTOMATIC SELF STARTER POR MOTORS. APPLICATIONIILED'APBLQ, 1904. RENBWED MAR. 29. 1912.

150432m/- Patented N0v.5,1912.

2 SHEETS-SHEET 2.

- UMTED srnrns riiivfr marion.,

HENRY CUTLER, O1?" MILWAUKEE, WISCONSIN.

Specification of Lessico?. i

AUTOMATIC SELF-STARTER FOR MOTORS.

Lesers Patent'. Patented Nev. 5, 1912.

Application filed pril 9, 1904, Serial No. 202,311. Renewed March 29,1,912.. Serial No. 687,27.

To all whom t may concern:

Be it Iknown that l, HENRY H. CI'TLER, a f citizenv of the UnitedStates, residing at Milwaukee, in the county of Milwaukee and 5 State ofll'visconsin, have invented new and useful Improvements in AutomaticSelt- Starters for Motors, of which the following is a full, clear,concise, and exact description, reference being had to the accompany-'ing drawing, forming, a part of this specification.

Iii-v invention relates to a self-starter for electric motors.11i-starters of this class a solenoid or electromagnet is usually em-15l ployed which, when energized, is adapted to' m'ove the Contact armof the starting box or lrlieostat across a series of terminals togradually remove the resistance from the armature circuit, therebygradually starting the motor. Then the Contact arm has been moved to theon position. itis usual to provide some means. for retaining the contactarm in this position without neces sitating the passageof'tlie fulloperating currentthroughthe windings of the solenoid. I Itis tlieobjectof the present invention to provide improved means for retaining thecontact arm. in the on position after the same has been moved theretothrough the agency of the operating solenoid.

-In accordance with my invention I provide supplemental electromagneticmeans for vretaining the contact arm in the on .',posi'tiom whereby theelectromagnetic means which serve to move the Contact arm to the onposition in starting the motor, may be disconnected from circuit. IpreferablyT provide a retaining electromagnet separate yand-distinctfr'oin the pulling electromagnet,

"40 'which serves tov move the contact arm, and -associate with thecontact arm suitable switching mechanism. whereby the winding of thepulling magnet is removed from circuit when the working stroke of thecon- 45 tactvarm has been completed.

`One form of apparatus tor carrying out my invention I have disclosed inthe accompanying drawings, in which:

,Figure 1 is a front elevation of my device; Fig. 2 is a side elevationthereof; and, Fig. is a diagrammatic view of the circuits?? einployed.'In the embodiment ofmy device which .I have worked out as the preferredconstruction, uponV an insulating base 1, of slate or marble. .or other.suitable materiali adapted to be secured to the wall or other verticalsupport, a resistance controlling solenoid 2 is mounted. The solenoid isprovided with a trame 3, having lugs or feet 4 bolted to the base l tosupport the solenoid. in position upon the base. Suitable rlieostatcontacts 5 are also secured upon'the base 1 by meansI of screws or inany other desired manner. A suitable operating'lever 6 carries a suit'-lable Vcarbon brush T atone end thereof,-l. which is'normally pressedupon resistance contacts-5 by the coiled spring 10 mounted upon the pin9. The lever is secureduppnl .l the plate 1 by means of a plate8'boltf'et to the base plate 1, having a projecting. p" upon which thelever 6 is pivoted. lever 6 has a rearwardly projecting arm' 11 to whichis attached the piston rod-12 of the dash-pot 13. The piston l-l of thedashpot 13 is provided with suitable ports 15 extending therethrough,which are adapted to be opened and closed by the movable plate or valve16, carried upon the lower end of the piston rod 12.'. At the lower endof '30 the dasli-pot 13 are provided by-passes 13a, having ports 13b and13C, which open into the chamber of the dash-pot. The dash-pot' 13 has asuitable 'projection 17, by which it is suitably pivoted.v as yat 18, toa downwardly extending plate 19.

The4 core 2O of the solenoid 2 is adjustablv secured at its lower end toa connecting link v 21, which is pivotally secured to the lever or arm 6and the upper end of the core is 90 adapted' .to move into engagementwith a coiieesliaped stop 22, secured in position by the nut 23, andwhich permits a uniform movement of the core and thereby the lever 6;pon the inner face of the arm or lever 6 is mounted a suitable springcontact 2l adapted to make engagement with an acljustable contact 25mounted upon the plate 1,whieh contact is electrically connected. withthe lastof the series of .contacts 5,100 thereby, when the lever is in'its tinal posir tion, relieving the lever of part of the motor currentand preventing the overheating of the lastcontact.

`Secured to the outer end of theleveijfis :105 a bracket. having arms 26and 27 extending-- overthe front end of the lever and over the.

upper sidev thereof being held in position; *f by screws 28, 28, andhaving at its outerand? upper` end a projection 29, to whichwisfll'magnet 31,- mounted upon the base plate 1, and having suitable magnetpoles 32 and 33. rlhe wedgosiiaped armature member 23 is adapted, whenattracted, to lit within the V-shaiied oiwning formed by the taperedsides 34 and 35 ot the magnet poles 32 -anc 33.

A binding post 3G is secured to the trout tace ot' the plate 1 and hassecured thereto by nut 37 one end ot a spring plate 38, which forms aswitch connection with a. second binding post 3l). rThe spring plate 33has downwardly extending projection 4() adapt.- ed to malte eoni'iectionwith the inclined tace 4.1, ot an adjustable contact 42, secured to thebinding post 3). lVhen the lever is in the full on position, a pin 43carried thereby is adapted to engage the spring` plate 38,. and morethel projection 4() out ot engagement with the contact 42.

vIn Fig. 3 the. circuits and other apparatus involved in the system areshown.' A solenoid switch 44 is employed tocoi1itrol the circuit to themotor 45 and any suitable switch 46 controls the operation ot the switch44. The plus andininus sides ot the power circuits are indicatedrespectively by the numerals 47 and 4.3/ A main switch 45) is providedtor closingv the circuit through thel several parts ivitlitlie mainline.

The operation qt'tie device would bons follows: Assuming the main switch49 and the switch to be closed, circuit may be traced from the'pliis'side of the line through conductor 47,;through the winding ot thesolenoid 445,;thrrmgh switch 4G, conductor 49, the first ot the seriesot' contar-,ts 5, contact lever C and back to the opposite main 48, byconductor 50. This energizes the winding ot' the solenoid and causescontact lplate 51 to eoimect'the terminals 52, 53.

Current will then low through the conductor 47, terminal 52, contactplate 51, terminal 53, conductor 54, conductor 55, through the windingof the solenoid 2 to terminal 39, across the switch 3S, throughconductor 56 and thence by conductor 50 to the opposite side 48 ot themain. At the same time circuit is closed by the operation of the contact51, through the field winding 5,7. of the motor and the circuit may betraced by conductor 47, across the switch 51, conductor 54, eld winding57, conductor 5S, through the winding ot the magnet 31, therebyenergizing the same through oonductor 59, and thence by conductor 50 tothe opposite main 48. The winding of the solenoid magnet 2 beingenergized, the Ysame will attract its core and move the lever 6 acrossthe contacts 5, 5, thereby cutting out the resistance 60 in the armaturecircuit and starting the vmotor in operation.

The lever 6 normally bridges the iirst two contacts and short ci its aresista-nce G1, which is inserted in the circuit of the wind- Lorano-ring of the solenoid 44, but as soon as the .lever is moved otl' thelliz-st ot the series of contacts 5, the resistance (5l is inserted incircuit, tlierel'iy decreasing the strength of the winding of thesolenoid 44 to such a degree thatI while it will serve to maintain theContact 51 in a closed position, if, for any reason, the current is cutotl', it will not again operate to close the switch. When the lever (3reaches the last position, cutting out all the resistance GO in themotor armature circuit., the pin 43 mounted thereon will engage theswitch 38, moving the same out ot Contact with the terminal 42 andthereby open the circuit through the winding ot' the solenoid 2. By thismeans only the retaining magnet 31 is retained in circuit across theline and this magnet is only ot' sntieient strength to hold the lever inits on position. A conductor (3 connects the hub of the contact arm (3with the second Contact, so that in case the contact between the contactarm and the contacts should be detective the armature current will stilltiptel a path through conductor (i and the resistance coils.

As the lever (l n'ioves across the series of contacts 5 the piston 15Will move downwardly into the dash-pot 13 andas the ports 15 are closedby this movement the move. ment ot' the lever will be retarded as theoil cannot freely pass around the piston. As soon, however, as thepiston reaches a point intermediate of the ports 13b and 13, the oilwill pass freely through the ley-pass 13 troni one side ot the piston tothe other, allowing the piston to move rapidly to the end of its stroke.At the saine time the ari'nature 3() carried by the lever G will be nearthe poles ot the magnet, 32 which will exerta slight pull on thearmature, thereby assisting the solenoid Q.. This causes a rapidmovement of the lever over the last part of its' movement and the switcharm '3S is rapidly caused to break contact with its contact 42, therebypreventing a reing at this point.

It Will thus be seen that I have provided means for automaticallystarting the motor as soon as the switch 46 is closed, but as soon asthemotor is started,l the pulling magnet is cut out of circuit and aretaining magnet only serves to hold the controller arm in the onposition. By this arrangement, as soon as the current, for any reason,is cut off from the field windings, the retaining magnet 31 will bedenergized and the same will permit the controller arm f3 to move to itsinitial position, through its own weight, the piston 14 offering butlittle resistance in this movement as the ports l5 are generi by thedownward movement of the ever and the oil is permitted to freely passtherethrough. f

lVhile I have shown and described one form ot' my invention. it Will beunderstood duce the current through the magnet to such' a degree thatthe same is only of sutlicient strength to hold `the operating lever inposition, but itwill be understood that I do not wish to limit myself tothis construction as there are numerous other ways of arrang- :ing theretaining magnet'and the pulling magnet without departing from thespirit of mykinvention. For instance, the retaining magnet may beconnected in an independentcircuit and 4suit-able resistance insertiwlto reduce its strength, or the retaining magnet maybe so arranged thatlits circuit may be closed only when the circuit is opened throughthepulling magnet, or the retaining magnet may be arranged in anindependent circuit which is normally open. but which is adapted to beclosed when the circuit of the -pulling magnet is opened. The abovearrangements are cited merely to show the .general changes which may, bemade in my device and-arel not intended to be an exhaustiveenumerat-ionof the various changes which may be made.

Having thus described my invention what I claim as new and desire tosecure by Letters Patent is:

1. In a starting device for electric motors, in combination, asupporting panel, a series of resistance contacts mounted thereon, faresistance varying element pivoted upon said base and carrying atl oneend a Spring pressed contact adapted to` engage and move over saidseries of ccntmts a solenoid mounted vertically on sald panel andhaving'a movable plunger connected to said element for operating thesame, a dashpot having its piston connected to a rearward extensionv onsaid element Vfor retarding the operation of said element in onedirection, a switch mounted on said panel between said element and saidsolenoid and arranged to be actuated by said element as itreaches thelimit of its movement to denergize said solenoid, a, retaining magnetmounted on said base contiguous to said solenoid, and a pivoted armaturecarried at the forward end of said element and arranged vto be attractedby said. retaining magnet to hold said element at the limit of itsmovement aft-er dcenergization of said solenoid.

2. In a starting device for electric motors, in combination, a series ofcontacts, a starting resistance connected thereto, an electromagnetic-ally operated switch arm movable over said contacts to controlsaid starting resistance, an electromagnetically operated main switch,said switch arm, when in its initialposition, being included-in andadapted to complete the circuit of the ope;v ating winding of said mainswitch, a resistance arranged to be short-circuited by said switcharmwhen in initial position, and to be inserted in circuit with 'theoperating winding of said main switch when said switch arm is actuated-to prevent reclosure of said main switch until said switch arm isreturned to initial position.

. In witness whereof, I have hereunto subscribed my name in the presenceof two witnesses.

. HENRY H. CUTLER. Witnesses:

F.S. WJLHorr, F. R. BACON.

